This article is concerned with the nature of individual moral failure. This has not been a standard issue for exploration in moral philosophy, where questions surrounding moral success have been more popular: in particular, the questions “What is it to do the moral thing ?” and “Why am I supposed to do the moral thing ?” I want to change the subject and pursue answers to three importantly related questions about people's failure to be moral. First, I want to explore an issue in moral psychology: why do people behave immorally? I suspect this question has been largely ignored by philosophers because they have thought it a question for psychologists, and one that, at any rate, has an easy surface answer. Isn't it our immorality simply the result of our excessive self-interest? Yet we shall see in what follows that this answer is not nearly good enough, and that philosophers have a lot to contribute in determining what would count as a satisfactory answer. We shall also see that different meta-ethical theories purporting to explain the authority of moral action implicitly assume different and often mutually inconsistent accounts of why we fail to be moral, and our analysis will show that none of these accounts of moral failure is unproblematic